Device for measuring liquids



May 7, 1940. L. J. A. CADET 0 DEVICE FOR MEASURING LIQUIDS Filed July 22. 1937 Patented May 7, 1940 DEVICE FOR MEASURING LIQUIDS Louis Jules Adrien Cadet, Le Vesinet, fiance, as-

signor to Socit Anonyme dlte: Socit dEtude de Distributeurs Automatiques S. E. D. 11.,

Paris (Seine), France Application July 22, 1937, Serial No. 155,098 In France October 8, 1936 1 Claim. (Cl. 73247) Known apparatus for measuring liquids of the so-called continuous meter .type, are constituted, substantially, by a plurality of identical pistons arranged, according to a known method a at equal angular distances apart relatively to each other, about a central shaft, these pistons effecting equal strokes.

In the known apparatus the movement of the pistons is controlled by a rotary distributor mov- 10 ing against a port face. With theknown app'a ratus, for a comparatively small output, the resistant torque offered by the distributor, that is to say, the stress pressing the distributor on its port face is very slight with the result that the fluid-tightness of the distributor is ineffective for these small outputs. 'Moreover, in the case of increasing output, the stress forcing the distributor on its port face increases rapidly with the resultant danger of jamming.

According to the present invention the stress applying the distributor to its port 'face is so regulated as to be considerable 'even for very. small outputs so that the fluid-tightness is eifectively maintained. For increasing output to a '35 predetermined value, the stress decreases slowly to a predetermined point from which it increases. gradually in a comparatively slow manner to insure high output without the risk of jamming.

In the accompanying drawing wherein an ap- Z21) proved embodiment of the invention is illustrated:

Figure 1 is a vertical sectional view through a measuring device constructed in accordance with the invention. I

:25 Figure 2 is a diagram showing the curve of the resistant torque of the distributor.

The measuring apparatus comprises a plurality of pistons l"(|."ll actuating, through connecting rods 9! and cranks 10, a shaft 2. On

. this shaft is rigidly secured the rotary distributor 5, which comprises an inlet opening 6 and an outlet opening i and'which moves on a port face provided with a series of ports 8 (l -4 A) corresponding to each of the pistons l (I -l The liquid is admitted through the connecting branch 3 and issues through the connecting branch 4 in the crankcase.

The compensation device constructed according to the invention comprises a piston ll mov- 50 ing in a cylinder l2 incommunication, at its lower part, with the'incoming liquid through the medium of a conduit, I IX, connecting the orifices "and It. At its upper part, the piston II is exposed to the pressure of the outgoing liquid 55 through an orifice llu. Under the eflect of the the other hand, on the shoulder I 5 of a member directly pressed against the shaft 2 and forming 5 a. foot step bearing. The spring (4 possesses a certain initial tension R, the increase in the force of the spring I4 due to compression by the piston ll being too small to warrant consideration in the following equation. The downward stroke of piston II is limited by an abutment l8 and its upward stroke is limited by a second abutment i1 forming one piece with the shoulder ii. The piston ll bears against this latter abutment l1 when the pressure P reaches a value P1 which depends, of course, on the cross section of the piston II and onthe initial tension R of the spring l4.

Assuming that S represents the value of the useful surface of the distributor 5 on which the pressure difference P is effectively exerted and that s represents the surface of piston H, the resulting stress on shaft 2, of the distributor, is equal:

For the values of P lower than P1; To R-PS decreasing when Pincreases, and for the values of P higher than P1;

To P (s-S) increasing with P if s is given a value higher than that of S.

In Fig. 2, the curve of the resistant torques of the distributor is indicated at E F, G, the point Co on the abscissae Po corresponding to the starting'of the meter.

What I claim as my invention and desire to secure by Letters Patent isi In a continuous meter, comprising: cylinders, pistons in these cylinders, ashaft driven by the combined action of said pistons, an inlet pipe line for the liquid, an outlet pipe line for the liquid, a 40 distributor in the shape of a cup fast onsaid shaft, the convexity of this cup being turned towards the outgoing liquid and the incoming liquid tending to unseat the distributor; an auxiliary cylinder, an auxiliary piston in the auxiliary 5 cylinder, connecting branches for connecting the two chambers of the auxiliary cylinder on opposite sides of the auxiliary piston with the incoming and outgoing liquid on opposite sides of the distributor, an abutment in said cylinder engaging said shaft, a calibrated spring taking a bearing on the auxiliary piston and pressing said abutment against the shaft of the'meter to press the distributor toward its seat.

' LOUIS JULES ADRIEN CADET. 5 

